An anchor for a watercraft

ABSTRACT

An anchor for a watercraft comprising a shank and at least one prong adapted for attachment to the shank, wherein the anchor for a watercraft also comprises at least one weakened connection configured to release the at least one prong from the shank when a load on the at least one prong exceeds a predetermined threshold.

TECHNICAL FIELD

The present invention relates to an anchor for a watercraft.

BACKGROUND ART

Known anchors for watercraft are designed for either seabed/reef or sand/mud but not specifically for both. Each anchor has its strengths and weaknesses. A seabed anchor must have prongs to secure itself into the seabed structure. It must have a “weak or failure point” to allow it to release and be retrieved. Some of these anchors have poor to moderate non-aggressive holding capabilities due to their blunt, thin prongs that need to bend under pressure to release while others on the market use items like plastic cable ties at their failure point to transfer their attachment point from the shank of the anchor to the head for easier retrieval. Some anchors have no failure point and rely on excessive power to rip themselves out of the seabed causing large amounts of damage. However, due to the potential for these anchors to get stuck in the seabed they are usually simplistic in their design and have poor holding capacity in shoals, sand and mud. The sand/mud anchors on the market are usually heavier, much more expensive and are not recommended to use on the seabed because they have a high potential to get stuck on the structure resulting in dangerous pressure on the bowsprit, losing the anchor and/or damaging the delicate corals etc. Some of these anchors have slides to assist in their release but it is not a failsafe system and many such anchors have had to have their ropes cut when they have become stuck losing not only the anchor but all their chain too.

It will be clearly understood that, if a prior art publication is referred to herein; this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.

SUMMARY OF INVENTION

The present invention is directed to an anchor for a watercraft, which may at least partially overcome at least one of the aforementioned disadvantages and/or provide the consumer with a useful or commercial advantage.

With the foregoing in view, the present invention in one form, resides broadly in an anchor for a watercraft comprising a shank and at least one prong adapted for attachment to the shank, wherein the anchor for a watercraft also comprises at least one weakened connection configured to release the at least one prong when a load on the at least one prong exceeds a predetermined threshold.

The anchor may be fabricated from any suitable material or combination of materials. For instance, the anchor may be fabricated from metal, such as aluminium, steel (such as stainless steel, galvanised steel, high tensile steel, etc.), cast iron, cast lead, or combinations thereof. Preferably however, the anchor may be fabricated from a material that is relatively resistant to corrosion. For example, at least a portion of the anchor may be fabricated from galvanised metal. It will be understood that the type of materials used to fabricate the anchor may vary depending on a number of factors, such as the size of the watercraft, the seabed type, and the holding conditions. The components of the anchor may be fabricated from the same type of material or from different types of material. For instance, in some embodiments of the invention, the anchor may include one or more flukes. In these embodiments, the flukes may be fabricated from standard mild steel and the shank may be fabricated from constructional steel. One or more components of the anchor may be ballasted, for instance by adding weight to the component or by reducing weight in the other components of the anchor. Preferably, the tip of the flukes or the end of the shank nearest the flukes may be ballasted.

In some embodiments of the invention, the anchor may be provided with a sacrificial portion so as to improve the corrosion resistance of the anchor. Any suitable sacrificial portion may be used, although in a preferred embodiment of the invention, the sacrificial portion may comprise a sacrificial anode. The sacrificial portion may be fabricated from any suitable material. Preferably, the sacrificial portion may be fabricated at least partially from zinc.

The anchor for a watercraft comprises a shank. The shank of the anchor may be of any suitable size, shape and configuration. The size and shape of the shank may vary, although it is envisaged the shank may be an elongate structure. The shank may have any suitable cross-sectional shape, such as circular, square, rectangular, triangular and so on. In some embodiments of the invention, the shank may be substantially linear, or may be curved or any other suitable non-linear shape. The shank may be a solid member, or may be hollow along at least a portion of its length.

In an embodiment of the invention, the shank may comprise a bore extending along at least a portion of the length of the shank. The bore may extend into the shank from a first end thereof, or from an opposing second end thereof. Preferably, the shank may comprise a bore extending along the entire length of the shank (i.e. from a first end to an opposing second end thereof). The bore may be of any suitable length and any suitable diameter. The diameter of the bore may be substantially constant along its length. The bore may comprise a pair of open ends, one open end and one closed end, or one open end and one partially closed end.

In an embodiment of the invention, the shank may be a unitary structure. In a further embodiment of the invention, at least a portion of the shank may comprise two or more shank portions connected to one another. In one embodiment, the shank suitably comprises a first shank portion and a second shank portion. Preferably, a first end of the first shank portion may be adapted to be at least partially received in a bore provided in the second shank portion and retained therein. In some embodiments of the invention, a portion of the first shank portion may be received and retained in the bore of the second shank portion, while in other embodiments of the invention substantially all of the first shank portion may be received and retained in the bore of the second shank portion. Preferably, the second shank portion, which may be configured to receive at least a portion of the first shank portion therein, may comprise a bore extending along the entire length of the shank (i.e. from a first end to an opposing second end thereof). The bore of the second shank portion may be of any suitable size, shape and configuration, preferably, however, the bore of the second shank portion may be configured such that the second shank portion may be capable of sliding at least partially along the length of the first shank portion.

In an embodiment of the invention the shank may comprise two or more shank portions wherein each of the shank portions is in frictional engagement with the other. In an embodiment of the invention, the first shank portion is adjustably engaged with the bore of the second shank portion, such that the first shank portion is capable of movement relative to the second shank portion. The first shank portion may be adapted for adjustable engagement with the second shank portion by any suitable means, such as, but not limited to, a screw threaded connection, telescoping connection, ratcheting connection, one or more locking members (such as pins) or the like.

The two or more shank portions may be frangibly attached by at least one weakened connection. For instance, the weakened connection may comprise a sacrificial mechanical fastener, a frangible coupling, spot welds, and the like. In an embodiment of the invention, the first shank portion and the second shank portion may be provided with one or more apertures that when aligned, a mechanical fastener may be inserted to connect the shank portions to one another. The mechanical fastener may be of any suitable size, shape or configuration. For instance, the locking member may comprise a mechanical fastener such as a lock pin, a shear pin, nut and bolt, screw, rivet, nail and the like. Preferably, the mechanical fastener may comprise a shear pin. It is envisaged that, in use, the weakened connection may connect the two or more shank portions until a load on the anchor, which exceeds a predetermined threshold, causes the first shank portion to move relative to the second shank portion, breaking the weakened connection and freeing the first shank portion to move relative to the second shank portion.

The anchor comprises at least one prong adapted for attachment to the shank. The prongs may be adapted for attachment to the shank by any suitable means. For instance, the prongs may be attached to the shank using one or more mechanical fasteners (screws, bolts, rivets, pins, or the like), may be welded to the shank using any suitable technique, or may be pivotally or hingedly mounted relative to the shank. In an embodiment of the invention, the prongs may be mounted so that they may move relative to the shank. For instance, each of the prongs may be mounted so as to be foldably, hingedly or slidably movable relative to the shank. Most preferably, each of the prongs may be pivotally mounted relative to the shank.

The at least one prong may be mounted to any suitable portion of the shank. For instance, the prongs may be mounted directly to the shank or to the one or more shank portions or mounted indirectly to the shank or to the one or more shank portions. In an embodiment of the invention, the at least one prong may be mounted directly to the shank or to the one or more shank portions. In an alternative embodiment of the invention, the at least one prong may be mounted to the shank by more than one mechanism. For instance, the at least one prong may be attached directly to an end of a first shank portion at one end of the prong and may be attached indirectly to an end of a second shank portion via an arm member. In a preferred embodiment of the invention, the at least one prong may be mounted indirectly to the shank or to the one or more shank portions.

In an embodiment of the invention, the shank may be provided with one or more arm members extending outwardly therefrom, wherein the one or more arm members may be configured for attachment to at least one prong. In this instance, it is envisaged that the arm members may be attached to the shank at one end thereof and to a prong at a second end thereof. The arm members may be spaced apart about the periphery of the shank in any suitable configuration. For instance, the arm members may be spaced apart substantially equidistant about the periphery of the shank, may be spaced apart such that the arm members may be positioned on one side of the shank, may be spaced apart at regular intervals, and any suitable combination thereof. The arm members may be attached to any suitable portion of the shank. Preferably, however, the arm members may be attached to a portion of the shank which enables the flukes of the anchor to dig into the seabed and facilitates movement of the prongs relative to the shank. Preferably, the arm members may be attached at or near an end of the shank. In an embodiment of the invention, wherein the shank comprises two or more shank portions, it is envisaged that the arm members may be attached to a lower portion of the shank portions such that the arm members are effectively attached at or near an end of the assembled shank. In an embodiment of the invention, the one or more arm members and the second shank portion form a single moulded body. In this instance it will be understood that the arm members may be fixed relative to the second shank portion.

The one or more arm members may be of any suitable size, shape and configuration. For instance, the arm members may be in the form of a pin arm, a bracket, a plate-like structure, a hollow extrusion, a multi-plate structure, etc. Preferably however, the arm members may be of a configuration that facilitates the pivotal movement of the at least one prong relative to the shank. The shank may be provided with one or more types of arm members. In an embodiment of the invention, the second end of the arm member may be provided with a substantially U-shaped configuration, wherein at least a portion of the prong may be received within the channel of the U-shape. In this instance, it is envisaged that each leg of U-shaped second end and prong may be provided with one or more apertures, through which, when the apertures are aligned, a mechanical fastener may be at least partially passed therethrough in order to connect prong to arm member. Preferably, the connection enables the prong to pivot relative to the arm member.

The arm members may be provided with one or more prongs. Any suitable number of prongs may be used, for instance, each arm member may be provided with a prong or alternatively, each arm member may be provided with two or more prongs. In an embodiment of the invention, a prong may be attached to two or more arm members. Alternatively, one or more arm members may not be provided with a prong. However, it will be understood, that the number of prongs used may vary depending on the type of watercraft, the type of seabed, and the size, shape and configuration of the prongs and flukes.

The prongs may be attached to any suitable surface of the arm members. For instance, the prong may be attached to a surface of arm member, to an end of an arm member, to two or more arm members, to adjacent arm members such that the prong is sandwiched between the arm members, to an inside surface of a hollow arm member, and any suitable configuration thereof. The prong may be attached at one or more points to the arm member. However, it will be understood that the surface of the arm member to which the prongs may be attached may vary depending on the type of arm member, the type of prong and the type of anchor. Preferably, the attachment of the prongs to the arm members may be sufficient to enable the prongs to move relative to the arm members.

The at least one prong may be attached to the arm member by any suitable means. For instance, the prongs may be attached to the arm members using one or more mechanical fasteners (screws, bolts, rivets, pins, or the like), may be welded to the arm members using any suitable technique, a pin arm and slot arrangement, or may be pivotally or hingedly mounted relative to the arm members. In an embodiment of the invention, the prongs may be mounted so that they may move relative to the arm members. For instance, each of the prongs may be mounted so as to be foldably, hingedly or slidably movable relative to the arm members. Most preferably, each of the prongs may be pivotally mounted relative to the arm members. In an embodiment of the invention, the prongs may be removably mounted relative to the arm members. In this instance, it is envisaged that providing the anchor with removable components may facilitate better stowage and transportation of the anchor, enable broken or damaged portions to be removed and replaced, or reconfigure the anchor for a different environment by changing the components.

The at least one prong may extend outwardly from any suitable portion of the shank or a component thereof. For instance, the at least one prong may extend outwardly from the shank, from a shank portion, from an arm member attached to the shank, or any suitable combination thereof. Preferably, the at least one prong extends from the shank via the arm member at an angle of between substantially 10° and substantially 80°. More preferably, the at least one prong extends from the shank via the arm member at an angle of between substantially 20° and substantially 60°. More preferably, the at least one prong extends from the shank via the arm member at an angle of between substantially 30° and substantially 50°. In some embodiments of the invention, the at least one prong extends from the shank via the arm member at an angle of substantially 30°. In some embodiments of the invention, the at least one prong extends from the shank via the arm member at an angle of substantially 45°. However it will be understood that the angle the at least one prong extends from the shank via the arm member may vary depending on a number of factors such as the type of anchor and the size, shape or configuration of the prongs and/or flukes.

The prong may be frangibly attached to the shank, a shank portion or an arm member attached to the shank by at least one weakened connection. For instance, the weakened connection may comprise a sacrificial mechanical fastener, a frangible coupling, spot welds, and the like.

In an embodiment of the invention, the prong and the arm member may be provided with one or more apertures that when aligned, a mechanical fastener may be inserted to connect the prong and arm member to one another. The mechanical fastener may be of any suitable size, shape or configuration. For instance, the locking member may comprise a mechanical fastener such as a lock pin, a shear pin, and the like. Preferably, the mechanical fastener may comprise a shear pin. It is envisaged that, in use, the weakened connection may connect the prong and the arm member until a load on the anchor, which exceeds a predetermined threshold, causes the prong to move relative to the arm member, breaking the weakened connection and freeing the prong to move relative to the arm member. In this instance, it is envisaged that the prong and the arm member remain attached when the weakened connection breaks. Alternatively, the weakened connection may be the only attachment means between the prong and the arm member. In this instance, it is envisaged that the prong may separate completely from the anchor when the weakened connection between the prong and the arm member breaks.

In an alternative embodiment of the invention, the prong and the shank or shank portion may be provided with one or more apertures that when aligned, a mechanical fastener may be inserted to connect the prong and the shank or shank portion to one another. The mechanical fastener may be of any suitable size, shape or configuration. For instance, the locking member may comprise a mechanical fastener such as a lock pin, a shear pin, and the like. Preferably, the mechanical fastener may comprise a shear pin. It is envisaged that, in use, the weakened connection may connect the prong and the shank or shank portion until a load on the anchor, which exceeds a predetermined threshold, causes the prong to move relative to the shank or shank portion, breaking the weakened connection and freeing the prong to move relative to the shank or shank portion. In an embodiment of the invention, the lower end of the prong may be attached to a lower end of the shank or shank portion by at least one weakened connection. In this instance, it is envisaged that the prong may also be attached to the shank by one or more arm members, such that the prong remains attached to the anchor when the weakened connection breaks. Alternatively, the prong may only be attached to the shank or the shank portion by the at least one weakened connection. In this instance, it is envisaged that the prong may separate completely from the anchor when the weakened connection between the prong and the shank or shank portion breaks.

In one embodiment, the shear pin has a diameter of greater than about 1 mm, greater than about 2 mm, greater than about 3 mm, or greater than about 4 mm, greater than about 5 mm. In some embodiments, the shear pine has a diameter of between about 3 mm and about 10 mm, between about 3 mm and about 7 mm, between about 3 mm and about 5 mm, or between about 6 mm and about 10 mm. In certain embodiments, the shear pin has a diameter of about 3 mm, about 4 mm, or about 5 mm. In one embodiment, the shear pin is formed of a metal or metal alloy. In some embodiments, the shear pin is formed of stainless steel or mild steel. In a preferred embodiment, the shear pin is formed of mild steel. In an embodiment, the shear pin is formed of zinc coated mild steel. The use of mild steel allows for the shear pin to decompose in the water and this a favourable environmental result compared to other practices.

In one embodiment, the predetermined threshold is at least about 50 kg, at least about 100 kg, at least about 180 kg, at least about 250 kg or at least about 100 kg. In some embodiments, the predetermined threshold is between about 5 kg and about 1000 kg, between about 10 kg and about 500 kg, between about 20 kg and about 250 kg, between about 50 kg and about 200 kg, between about 50 kg and about 60 kg, between about 100 kg and about 120 kg, between about 180 kg and about 200 kg.

In an embodiment of the invention, the arm member and the shank or shank portion may be provided with one or more apertures that when aligned, a mechanical fastener may be inserted to connect the arm member and the shank or shank portion to one another. The mechanical fastener may be of any suitable size, shape or configuration. For instance, the locking member may comprise a mechanical fastener such as a lock pin, a shear pin, and the like. Preferably, the mechanical fastener may comprise a shear pin. It is envisaged that, in use, the weakened connection may connect the arm member and the shank or shank portion until a load on the anchor, which exceeds a predetermined threshold, causes the arm member to move relative to the shank or shank portion, breaking the weakened connection and freeing the arm member to move relative to the shank or shank portion. In this instance, it is envisaged that the prong attached to the arm member may also be attached to the shank, such that the prong remains attached to the shank when the weakened connection breaks. Alternatively, the prong may only be attached to the arm member. In this instance, it is envisaged that the prong and arm member may separate completely from the anchor when the weakened connection between the arm member and the shank or shank portion breaks.

The prong may comprise one or more flukes. For instance, each prong may comprise a fluke attached to a surface of the prong, two flukes positioned on either side of the prong such that they form a substantially solid shape, two or more flukes located on the prong such that they retain substantially separate forms, or any suitable combination thereof. In an embodiment of the invention, the prong and the flukes may be a substantially unitary structure. In an alternative embodiment of the invention, the prong and the flukes may be fastened together to form a composite structure. The prong and the flukes may be fastened together using one or more mechanical fasteners (screws, bolts, rivets, pins, or the like), an adhesive, a heat or chemical treatment, or welded using any suitable technique. Alternatively, the prong and the flukes may be fastened together by frictional engagement, or by providing complementary screw-threaded portions, press fittings, snap fit features, male-female connectors, or the like.

The fluke may be of any suitable shape, size and configuration. For instance, the fluke may have a cross-section that is substantially triangular-shaped, diamond-shaped, palm-shaped, plough-shaped, spade-shaped, and the like. Preferably however, the fluke comprises a tip portion or a pointed projection. In use, the tip portion penetrates into the seabed enabling the anchor to hold the watercraft in position. The tip portion may be ballasted to aid in penetration of the seabed.

The fluke may have a substantially flat surface, a substantially concave surface, a substantially convex surface, or combinations thereof. In an embodiment of the invention, a first portion of the fluke may comprise a first surface configuration and a second portion of the fluke may comprise a second surface configuration. However, it will be understood that the size, shape and configuration of the fluke may vary depending on the type of watercraft, the seabed type and the holding conditions.

Preferably, the fluke extends from opposing sides of each prong at an angle of at least substantially 60°, at least substantially 70°, at least substantially 80°, at least substantially 90°, at least substantially 100°, at least substantially 110°, at least substantially 120°. Yet more preferably, the fluke extends from opposing sides of each prong at an angle of at least substantially 90°.

In some embodiments of the invention, the anchor may be provided with the same types of prongs or different types of prongs. In this instance, it will be understood that the prongs may be of the same size, shape or configuration or may be of different sizes, shapes, or configurations. For instance, the prong-shank angle may be the same, or may be different. For instance, the anchor may comprise one or more prongs suitable for reef anchoring and one or more prongs suitable for sand anchoring. In some embodiments of the invention, the anchor may be provided with the same types of flukes or different types of flukes. In this instance, it will be understood that the flukes may be of the same size, shape, or configuration or may be of different sizes, shapes, or configurations. For instance, the fluke-shank angle and/or the fluke-prong angle may be the same, or may be different. For instance, the angle of the penetration edge of each fluke may be the same, or may be different.

The prongs may be arranged about the periphery of the shank in any suitable combination, for instance, the arrangement may be symmetrical about the longitudinal axis of the shank, or may be asymmetrical.

The first shank portion and the second shank portion may be provided with one or more stop members to preclude the first shank portion from passing fully into or out of the bore of the second shank portion. In an embodiment of the invention, the first shank portion may include at least one stop member extending outwardly therefrom. Any suitable stop member may be provided, although in a preferred embodiment of the invention, the stop member may comprise a flange. In an embodiment at least one flange may be located on an external surface of the first shank portion. It is envisaged that a flange located on an external surface of the first shank portion or at an end of the first shank portion may preclude the first shank portion from passing fully into the bore of the second shank portion. Thus, it is envisaged that the flange may extend outwardly from the surface of the first shank portion such that the diameter of the first shank portion (including the flange) is at least equal to the diameter of the bore of the second shank portion. The flange may extend at least partially about the circumference of the first shank portion. More preferably, the flange may extend about substantially the entire circumference of the first shank portion. Thus, in some embodiments of the invention, the flange may be an annular flange.

In an alternative embodiment of the invention, at least one stop member may be located in the bore of the second shank portion. Preferably, the stop member is located in the bore towards the first end of the first shank portion. It is envisaged that a stop member in the bore of the second shank portion may prevent the first shank portion from passing through the bore in the second shank portion. The stop member may be of any suitable form. In some embodiments of the invention, the stop member may comprise a projection, flange, shoulder or the like or any suitable combination thereof.

In an embodiment of the invention, the stop member for the first shank portion comprises an end member. For instance, the end member may comprise a cap, a plug, a collet, or the like. The size, shape and configuration of the end member may vary, providing that the end member may at least function to preclude movement of the prongs of the anchor relative to the arm members of the anchor. The end member may be fabricated from the same type of material as the anchor or from a different type of material.

Preferably, the end member may be adapted for removable attachment to the shank. For instance, the end member may be retained in removable attachment with the shank by frictional engagement, or by providing complementary screw-threaded portions, press fittings, snap fit features, male-female connectors, or combinations thereof. In some embodiments of the invention, the end member may be permanently attached to the shank or shank portion. Preferably, the end member may be screw-threadedly engaged with the bore of the shank or shank portion.

In an embodiment of the invention, the end member may comprise at least one projection extending outwardly therefrom. Any suitable projection may be used, although in a preferred embodiment of the invention, the projection may comprise a flange. In an embodiment of the invention, at least one flange may be located on an external surface of the end member. Preferably, the flange may be located on an external surface of the end member towards an end of the end member, or located at the end of the end member. The flange may extend at least partially about the circumference of the end member. More preferably, the flange may extend about substantially the entire circumference of the end member. Thus, in some embodiments of the invention, the flange may be an annular flange. In this way, the flange of the end member substantially precludes pivotal movement of the prongs of the anchor relative the arm members of the anchor and prevents the first shank portion from passing fully out of the bore of second shank portion. In some embodiments of the invention, movement of the first shank portion dislodges the end member, freeing the prongs to pivot relative to the arm members of the anchor.

The anchor may comprise an attachment end at an upper end of the shank or a shank portion. The anchor may be attached to an anchor rode, such as a chain or rope using an attachment point. Suitable attachment points include swivel connectors, shackle pins, and the like.

The anchor may comprise a tripping ring for a tripline to assist in recovery of the anchor or a component of the anchor. The tripping ring may be attached to one or more prongs, one or more arm members, the shank or a shank portion of the anchor.

The anchor may be used with any suitable watercraft. For instance, the anchor may be used with motorised or non-motorised watercraft, such as, but not limited to, boats, ships, personal watercraft (such as jetskis), submarines, houseboats, speedboats, barges, dinghys, rowboats, sailboats, catamarans, rafts, lifeboats, gondolas, kayaks, canoes, inflatable boats, and the like. Alternatively, the anchor may be used with a buoyant device, such as, but not limited to, floats, pontoons, floating docks, pontoon bridges, rafts, raft-like platforms, and the like.

The present invention provides a number of advantages over the prior art. For instance, the present invention enables the anchor to quickly penetrate the seabed, reducing damage to the seabed and more accurately mooring the watercraft. In addition, the present invention has a reduced environmental impact as the weakened connection points enable the anchor to be released when the load on the anchor exceeds a predetermined threshold. The present invention also avoids the use of non-biodegradable materials such as plastic zip-ties which can be left behind in the fishing grounds to reduce environmental impact. The present invention also provides an advantage over the prior art in that it can be broken down into pieces for stowage, different types of prongs and flukes may be added to enable the anchor to be used for different purposes and facilitate the replacement of damaged prongs and flukes.

In another form, the invention resides in a method of releasing an anchor for a watercraft including:

-   -   providing an anchor for a watercraft comprising a shank, at         least one prong adapted for attachment to the shank, and at         least one weakened connection configured to release the at least         one prong from the shank when a load on the at least one prong         exceeds a predetermined threshold;     -   subjecting a load greater than the predetermined threshold on         the at least one prong,     -   to thereby release the anchor.

The anchor is suitably as described hereinabove and hereinbelow.

Any of the features described herein can be combined in any combination with any one or more of the other features described herein within the scope of the invention.

The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge.

Reference throughout this specification to ‘one embodiment’ or ‘an embodiment’ means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases ‘in one embodiment’ or ‘in an embodiment’ in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

BRIEF DESCRIPTION OF DRAWINGS

Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows:

FIG. 1 shows a side view of an embodiment of the present invention in the form of an anchor for a watercraft.

FIG. 2 shows a side view of the present invention shown in FIG. 1 with the shear pin removed and shank separated.

FIG. 3 shows a side view of the present invention shown in FIG. 1 in disassembled form.

FIG. 4 shows a side view of an embodiment of the present invention in the form of an anchor for a watercraft.

FIG. 5 shows a top view of the present invention shown in FIG. 4

FIG. 6 shows a bottom view of the present invention shown in FIG. 4 .

FIG. 7 shows a side view of an embodiment of the present invention in the form of an anchor for a watercraft.

FIG. 8 shows a bottom end perspective view of the present invention shown in FIG. 7 .

FIG. 9 shows a top end perspective view of the present invention shown in FIG. 7 .

FIG. 10 shows a side view of the present invention shown in FIG. 7 with flukes in a position of reduced resistance.

FIG. 11 shows a view of the present invention shown in FIG. 7 in disassembled form.

FIGS. 12A and 12B show a view of an anchor according to an embodiment of the present invention where opposing prongs have a different configuration.

FIG. 13A shows a perspective view of an anchor according to an embodiment of the present invention.

FIG. 13B shows a bottom view of the anchor of FIG. 13A.

FIG. 13C shows a side view of the anchor of FIG. 13A.

FIG. 13D shows another side view of the anchor of FIG. 13D.

FIG. 14A shows an embodiment of a prong.

FIG. 14B shows the body portion of the prong shown in FIG. 14A.

FIG. 14C shows the fluke of the prong shown in FIG. 14A.

FIG. 15A shows another embodiment of a prong.

FIG. 15B shows the body portion of the prong shown in FIG. 15A.

FIG. 15C shows the fluke of the prong shown in FIG. 15A.

DESCRIPTION OF THE EMBODIMENTS

FIGS. 1 to 3 illustrate an anchor 100 for a watercraft, according to a first embodiment of the present invention. The anchor 100 generally comprises a shank 1 comprising two shank portions 1A, 1B, wherein the shank portions are telescopically engaged. It is envisaged that, in use, first shank portion 1A may be slidably engaged in second shank portion 1B in a telescoping fashion, such that first shank portion 1A is at least partially received and retained in second shank portion 1B. The first shank portion 1A and second shank portion 1B may be frangibly attached by at least one locking mechanism in the form of shear pin 9. It is envisaged that in use, shear pin 9 prevents second shank portion 1B from moving relative to first shank portion 1A until a load on the anchor 100 exceeds a predetermined threshold. When the shear pin 9 breaks, second shank portion 1B slides relative to first shank portion 1A.

Anchor 100 further comprises one or more arm members 6 attached to a lower end of second shank portion 1B and at least one prong 4 extending outwardly therefrom. In the present embodiment, anchor 100 comprises four arm members 6 attached to a lower end of second shank portion 1B and a prong 4 extending outwardly from each of the arm members. Each arm member 6 is spaced apart about the periphery of second shank portion 1B and fixedly attached thereto. Prongs 4 are pivotally connected to each arm member 6 by a mechanical fastener 7 at a first end and comprise a fluke 5 at the opposed second end.

Anchor 100 further comprises an end member 8 located at the lower end of first shank portion 1A and screw-threadedly engaged therewith. End member 8 comprises a flange extending outwardly therefrom, wherein the flange substantially precludes pivotal movement of the prongs 4 relative to the arm members 6 and prevents first shank portion 1A from passing fully out of the bore of second shank portion 1B.

In use, when anchor 100 is subjected to excessive load on the prongs 4 and/or flukes 5, shear pin 9 shears off, enabling sliding movement of second shank portion 1B relative to first shank portion 1A, this frees prongs 4 to pivot about mechanical fastener 7 and the flukes 5 are oriented in a position of reduced resistance enabling the anchor to be freed from the seabed. Advantageously, freeing shank portions 1A,16 to move relative to one another enables anchor 100 to be freed from the seabed without the anchor separating into separate parts which need to be retrieved from the seabed.

Each prong 4 forms an angle of between substantially 90° relative to the shank 1 for effective anchorage in a seabed or reef. A penetration edge 5A of each fluke 5 extends at an angle of between substantially 45° and substantially 135° from each opposing side of the prong 4 for effective mud or sand anchorage.

Anchor 100 further comprises an attachment end 3 at an upper end of the first shank portion 1A. The attachment end 3 of anchor 100 may be connected to a chain using an attachment portion such as a swivel connector 2. A tripping ring (not shown) for a tripline may be attached to an arm member, the shank and/or a shank portion of the anchor 100.

FIGS. 4 to 6 shows an anchor 200 for a watercraft, according to a second embodiment of the invention. Anchor 200 comprises a shank 11, four arm members 16 spaced about the periphery of a lower end of shank 11 and extending outwardly therefrom, a prong 14 pivotally connected to each arm member 16 by a mechanical fastener 17 and frangibly attached thereto by a locking mechanism in the form of a shear pin 19, wherein the prong 14 comprises a fluke 15.

Anchor 200 may comprise an attachment end (not shown) at an upper end of the shank 11 for attaching the anchor to a chain. A tripping ring (not shown) for a tripline may be attached to an arm member, the shank and/or a shank portion of the anchor.

In use, when anchor 200 is subjected to excessive load on the prongs 14 and/or flukes 15, the shear pin 19 shears off, which frees prongs 14 to pivot about mechanical fastener 17 orienting flukes 15 in a position of reduced resistance and enabling the anchor to be freed from the seabed.

FIGS. 7 to 11 illustrate an anchor 300 for a watercraft, according to a third embodiment of the present invention. Anchor 300 generally comprises a shank 21 comprising two shank portions 21A, 21B, wherein the shank portions are telescopically engaged. It is envisaged that, in use, a first shank portion 21A may be slidably engaged in a second shank portion 21B in a telescoping fashion, such that the first shank portion 21A is at least partially received and retained in the second shank portion 21B. The first shank portion 21A and second shank portion 21B may be frangibly attached by at least one locking mechanism in the form of a shear pin 29. It is envisaged that in use, shear pin 29 shears when a load on the anchor 300 exceeds a predetermined threshold. When the shear pin 29 breaks, the first shank portion 21A slides relative to the second shank portion 21B such that it is at least partially extended from the upper end of second shank portion 21B.

Anchor 300 further comprises four arm members 26 spaced about the periphery of a lower end of shank portion 21B and extending outwardly therefrom, a prong 24 pivotally connected to each arm member 26 by a mechanical fastener 27. Each arm member 26 is attached to second shank portion 21B at one end thereof and to prong 24 at a second end 30 thereof. Preferably, second end 30 of arm member 26 is configured to receive at least a portion of prong 24 therein, wherein second end 30 of arm member 26 has a substantially U-shaped configuration and at least a portion of prong 24 is received within the channel of U-shaped second end 30. Each leg of U-shaped second end 30 and prong 24 are provided with one or more apertures, through which mechanical fastener 27 may be passed when the apertures are aligned in order to connect prong 24 to arm member 26.

Anchor 300 further comprises an end member 28 in the form of a flange located at the lower end of first shank portion 21A and frictionally engaged with the lower end of second shank portion 21B. In this instance, it is envisaged that the flange 28 prevents first shank portion 21A from passing fully into or out of the bore of second shank portion 21B. In addition, flange 28 may substantially precludes pivotal movement of the prongs 24 relative to the arm members 26 whilst it is abutting projection 31 of prong 24.

Prong 24 comprises a fluke 25 which is configured to penetrate into the seabed enabling anchor 300 to hold the watercraft in position. Each prong 24 forms an angle of between substantially 90° relative to the shank 21 for effective anchorage in a seabed or reef. A penetration edge 25A of each fluke 25 extends at an angle of between substantially 45° and substantially 135° from each opposing side of the prong 24 for effective mud or sand anchorage.

Anchor 300 further comprises an attachment end 23 at an upper end of the first shank portion 21A. Attachment end 23 of anchor 300 may be connected to a chain using an attachment portion. A tripping ring (not shown) for a tripline may be attached to an arm member, the shank and/or a shank portion of the anchor 300.

In use, when anchor 300 is subjected to excessive load on prongs 24 and/or flukes 25, shear pin 29 shears off, enabling second shank portion 21B to slide along the length of first shank portion 21A. Consequently, prongs 24 are freed to pivot about mechanical fastener 27 and the flukes 25 are oriented in a position of reduced resistance enabling the anchor to be freed from the seabed. In use, it is envisaged that when the shear pin breaks, the prongs of the anchor pivot outwards past 90° and rotate back towards the axis of the shaft (see FIG. 10 ).

In FIGS. 12A and 12B, an anchor 400 comprising two pairs of prongs having a different size, shape and configuration are shown. In FIG. 12A, a first pair of prongs 32A, 32B having a more acute fluke-shank angle compared to a second pair of prongs (FIG. 12B) is illustrated. In use, it is envisaged that an anchor comprising an opposing pair of prongs 34A, 34B each having a shallower piercing entry (a larger fluke-shank angle) compared to the opposing pair of prongs may create less resistance at the entry point for the shallow prongs and improve penetration and holding capabilities of the shallow prongs.

Shown in FIG. 13 a illustrates an anchor 500 for a watercraft, according to a further embodiment of the present invention. FIG. 13 b shows an underside view of anchor 500. Anchor 500 comprises a shank, four arm members 560 spaced about the periphery of a lower end of the shank and extending outwardly therefrom, and a prong pivotally connected to each arm member 560 by a mechanical fastener 570. In one embodiment, the shank comprises two shank portions 510A, 510B wherein the shank portions 510A, 510B are telescopically engaged. In use, a first shank portion 510A is suitably engaged in a second shank portion 510B in a telescopic fashion, such that the first shank portion 510A is at least partially received and retained in the second shank portion 510B. The first shank portion 510A and second shank portion 510B may be frangible attached by at least one locking mechanism. In one embodiment, the at least one locking mechanism comprises a shear pin 590. The at least one locking mechanism is adapted to shear when a load on the anchor 500 exceeds a predetermined threshold. It will be appreciated by the person skilled in the art that the predetermined threshold can be any suitably threshold and may be adapted to a particular ocean floor landscape.

Anchor 500 further comprises an end member 580. The end member is located at the lower end of first shank portion 510A. End member 580 comprises a flange extending outwardly therefrom, wherein the flange substantially precludes pivotal movement of the prongs relative to the arm members 560 and prevents the first shank portion 510A from passing fully out of the bore of the second shank portion 510B. When the locking mechanism breaks, the first shank portion 510A slides relative to the second shank portion 510B such that it is at least partially extended from the upper end of the second shank portion 510B.

The anchor may suitably comprise prongs of different sizes and/or dimensions. In the embodiment shown, the anchor 500 comprises prongs 540 a and 540 b. In a preferred embodiment, the anchor 500 comprises two pairs of opposing prongs 540 a, 540 b. That is, prongs 540 a are adjacent prongs 540 b and prongs 540 b are adjacent prongs 540 a.

Each prong suitably comprises a fluke and a body portion. Prong 540 a suitably comprises a body portion 542 a and a fluke 545 a. In one embodiment, the fluke 545 a is generally perpendicular to the body portion 542 a. The body portion suitably comprises an aperture (not shown). The arms suitably comprise aperture(s) that are aligned with the apertures of the body portion. The mechanical fastener is suitably inserted into the apertures to facilitate pivotal movement.

Suitably, the prongs form an angle between the outer surface of the body portion and the outer surface of the fluke. In one embodiment, the angle is between about 45° and about 75°, between about 50° and about 70°, between about 60° and about 70°, between about 65° and about 70°. In the embodiment shown, the angle between the outer surface of the body portion and the outer surface of the fluke is 68°.

The other prong suitably comprises a fluke and a body portion. Prong 540 b suitably comprises a body portion 542 b and a fluke 545 b. In one embodiment, the fluke 545 b is generally perpendicular to the body portion 542 b. The body portion suitably comprises an aperture (not shown). The arms suitably comprise aperture(s) that are aligned with the apertures of the body portion. The mechanical fastener is suitably inserted into the apertures to facilitate pivotal movement.

Suitably, the prongs form an angle between the outer surface of the body portion and the outer surface of the fluke. In one embodiment, the angle is between about 45° and about 90°, between about 60° and about 90°, between about 70° and about 90°, between about 75° and about 85°. In the embodiment shown, the angle between the outer surface of the body portion and the outer surface of the fluke is 80°.

In an embodiment, the fluke and body portion of a prong can be integrally formed. In another embodiment, the fluke may be attached to the body portion. In this embodiment, the fluke is suitably permanently affixed to the body portion. In a further embodiment, the fluke is welded to the body portion.

In one embodiment, the flukes are diamond shaped. However, it will be appreciated by the person skilled in the art that the flukes can be any shape or size based on the area it is to be utilized. In this regard, diamond shaped flukes are believed to be used best in sand and/or mud.

The inventor postulate that having a different pair of prongs allow for a different angle of entry into the ocean floor. The non-symmetrical design creates an imbalance of penetration pressure on the prongs that drag along the ocean floor when the anchor is deployed. This imbalance results in one prong penetrating the floor prior to the other, and this creates a twisting motion. The inventor believe that this allows the anchor to further bury itself deeply into the floor.

Shown in FIG. 14 a is an embodiment of prong 540 a. Prong 540 a comprises a body portion 542 a and a fluke 545 a. Shown in FIG. 14 b is a side view of the body portion 542 a and shown in FIG. 14 c is a bottom view of fluke 545 a. The figures depict the angles and dimension of one embodiment of the prong 540 a.

Shown in FIG. 15 b is an embodiment of prong 540 b. Prong 540 b comprises a body portion 542 b and a fluke 545 b. Shown in FIG. 15 b is a side view of the body portion 542 b and shown in FIG. 15 c is a bottom view of fluke 545 b. The figures depict the angles and dimension of one embodiment of the prong 540 b.

As shown, prong 540 a has a more acute fluke-shank angle compared to prong 540 b. In this regard, it is postulated that an anchor comprising opposing prongs of 540 a, 540 b create a twisting motion of the anchor. As the anchor is burying or ‘grabbing’ the seafloor, it is postulated that the anchor better penetrates the seafloor, and this improves the holding capability of the anchor.

The person skilled in the art will appreciate that the anchors described herein may have any number of arm members and prongs. In this regard, the anchor may comprise one or more arm members and prongs. In one embodiment, the anchor comprises 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 arm members or prongs. Preferably, the person skilled in the art will appreciate that the number of arms is equal to the number of prongs. In a preferred embodiment, the anchor comprises four arm members. Testing

Testing was preformed on a number of differently sized shear pins to determine the predetermined threshold. The prongs of an anchor of the present invention were attached to an immovable objection to replicate the anchor being fouled on underwater landscape. Increasing pressure was applied with a lifting device attached to a crane scale, which was attached to the connection end of the shaft of the anchor until the shear pins sheared and the anchor collapsed. The shear pins were formed from zinc coated mild steel. The results are shown in Table 1:

TABLE 1 Shear pin diameter Pressure range at collapse Boat size, suitable for 3 mm 50 kg-60 kg 3 m-5 m 4 mm 100 kg-120 kg 5 m-9 m 5 mm 180 kg-200 kg  7 m-10 m

As shown, the present anchor can be adapted to be used by differently sized watercrafts by altering the shear pin diameter. It will be appreciated by the person skilled in the art that large shear pins than those shown above can be utilized for larger watercrafts.

It is envisaged that the shear pin diameter can be scaled to accommodate larger watercrafts. In this regard, in one embodiment, the shear pine has a diameter of between about 6 mm and about 10 mm.

In the present specification and claims (if any), the word ‘comprising’ and its derivatives including ‘comprises’ and ‘comprise’ include each of the stated integers but does not exclude the inclusion of one or more further integers.

Reference throughout this specification to ‘one embodiment’ or ‘an embodiment’ means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases ‘in one embodiment’ or ‘in an embodiment’ in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims (if any) appropriately interpreted by those skilled in the art. 

1. An anchor for a watercraft comprising: a shank; at least one prong adapted for attachment to the shank; and at least one weakened connection configured to release the at least one prong from the shank when a load on the at least one prong exceeds a predetermined threshold.
 2. The anchor for a watercraft according to claim 1, wherein the shank comprises two or more portions and wherein a first shank portion is frangibly attached to the second shank portion by the at least one weakened connection.
 3. The anchor for a watercraft according to claim 1, wherein the prong is frangibly attached to the shank by at least one weakened connection.
 4. The anchor according to claim 1, wherein the at least one weakened connection comprises or is a shear pin.
 5. The anchor according to claim 2, further comprising a stop member to preclude the first shank portion from passing through the second shank portion.
 6. The anchor according to claim 5, wherein the stop member comprises an outward extending flange.
 7. The anchor according to claim 6, wherein the flange is adapted to preclude movement of the at least one prong.
 8. The anchor according to claim 1, where the anchor comprises two or more different dimensioned prongs.
 9. The anchor according to claim 8, wherein each prong is adjacent different dimensioned prongs.
 10. The anchor according to claim 1, each of the at least one prong is pivotally hinged to the shank.
 11. The anchor according to claim 1, wherein the shank comprises a plurality of arms adapted to pivotally hinge at least one prong.
 12. The anchor according to claim 1 comprising a first set of prongs and a second set of prongs, wherein the first set of prongs have a more acute fluke-shank angle compared to the second set of prongs.
 13. The anchor according to claim 1 when used with a watercraft.
 14. A method of releasing an anchor for a watercraft including: providing an anchor for a watercraft comprising a shank, at least one prong adapted for attachment to the shank, and at least one weakened connection configured to release the at least one prong from the shank when a load on the at least one prong exceeds a predetermined threshold; subjecting a load greater than the predetermined threshold on the at least one prong, to thereby release the anchor.
 15. The method of claim 14, wherein the predetermined load causes the at least one weakened connection to break which facilitates release of the at least one prong. 